If Congressional leaders carry through on their threat to shut down the Department of Homeland Security (DHS), life for the agency's cybersecurity professionals -- and many others -- will be miserable. Many will be called into work. But they won't be paid, they won't know when they will be paid, and they will be forced to work under less than ideal conditions.

The DHS's mission of protecting life and property will likely ensure that its day-to-day operations continue, but everything that surrounds those duties may stall, including some investigations.

U.S. House leaders would fund DHS if the bill also includes provisions that kill most of President Barack Obama's executive orders on immigration. That measure, however, has been stymied in the Senate. If no agreement is reached, te department will shut down on Feb. 27.

The government shut down from Oct. 1-16, 2013 after Congress reached a budget impasse. Many government employees, however, worked without pay during that period.

Something to consider is the "unquantifiable psychological impact" that has on employees, said Hayes.

We need to keep people "motivated and passionate about what they do," said Hayes, "and any kind of sequester is going to have a negative impact into how much effort is put into protecting this country from a cyber-perspective,."

One area that may be particularly hard hit is the U.S. Secret Service, which is key in tracking a lot of financial fraud that occurs. "So having any cutback there will cause, perhaps, businesses to lose money," said Hayes.

At a hearing last Thursday by the subcommittee on Cybersecurity, Infrastructure Protection, and Security Technologies, U.S. Rep. Bennie Thompson (D-Miss.), the full committee's ranking member, outlined some of the impacts, including to DHS's nuclear protection office, which issues grants for nuclear detection. A shutdown would halt R&D development work on countermeasures to biological threats, on nuclear detection equipment and on cargo and passenger screening technologies, he said.

A large number of DHS employees "will be forced to [work] without pay," said Thompson, "creating a significant distraction and dealing a tremendous blow to a department with already low morale."

Allan Paller, director of research at the SANS Institute, said a direct effect of a shutdown would be "the loss of alerts that go out to agencies when their systems are sending unwanted data, which means they are almost certainly infected."

Among those working without pay will be 50,000 Transportation Security Administration workers, 13,000 immigration and customs enforcement agents, and 4,000 Secret Service employees. More than 40,000 border patrol agents will also work without paychecks.

In the 2013 shutdown, DHS kept in operation anything related to safety of human life and protection of property. That ought to include cybersecurity, said Samuel Visner, senior vice president and general manager for ICF's cybersecurity business ICF International, an IT services firm whose work includes homeland security.

The operational or day-to-day efforts to protect the nation from attacks would continue. But a shutdown could diminish or delay development of new proposals, new systems, and payments to industrial partners working in these areas, said Visner.